Semiconductors have permeated into every aspect of modern society. They are the building blocks used to create everything from the information super-highway to the electronic timer in the family toaster. Generally, any device that is used today that is considered “electronic” utilizes semiconductors. These often-unseen entities help to reduce the daily workload, increase the safety of our air traffic control systems, and even let us know when it is time to add softener to the washing machine. Modem society has come to rely on these devices in almost every product produced today. And, as we progress further into a technologically dependent society, the demand for increased device speeds, capacity and functionality drive semiconductor manufacturers to push the edge of technology even further.
A substantial amount of the semiconductors produced today are slated for the computer industry either as internal components or display components. Often, what we associate as “computer related” devices are used separately in products found in every day use. Flat panel screens are found in TV sets, handheld games, and even refrigerators. Computer chips are found in toasters, cars and cell phones. All of these common devices are possible due to the semiconductor. As the demand for more enhanced products increases, manufacturers must produce higher quality and, at the same time, cheaper semiconductor devices.
A growing area of manufacturing concentration has been on those components which can provide a building block for higher-level applications. These may include such components as memory, light emitting diodes (LEDs) and other semiconductor cells. Memory cells, for example, are used to store information. This simple device is found in some of the world's fastest computers and the most sophisticated electronics. Being able to store information, allows society to reuse data repeatedly. At the start of the electronic revolution, only a few bits of information could be stored. Today, we coin new words, such as gigabyte and terabyte, to describe the magnitude of the amount of information that can be stored, beyond most people's imaginations. This push towards larger and faster information storage and retrieval requires that semiconductors must be continuously improved to keep up with demand. LEDs have likewise pervaded our society as memory semiconductors have. They are used in displays, signs and signaling devices. They also continue to be revised, improved and advanced to keep in pace with our growing appetite for technology.
Although semiconductors (such as EEPROMs) have traditionally been based on inorganic materials during the fabrication processes, organic materials have begun to spread into the semiconductor manufacturing facilities. Organics offer the ability to produce more efficient and enhanced semiconductor devices. Organic semiconductor material (OSM) devices are being produced as a means to extend the production capabilities of present facilities. Devices that were thought to be reaching their molecular limitations as their sizes diminished, are finding new life through the use of OSM. Because of this renewing manufacturing effect, great emphasis has been placed on developing better OSM technology.
This trend in semiconductor devices has pushed organic entities such as OSM memory and organic LEDs (OLEDs) to become the new standards in semiconductor manufacturing over their former inorganic counterparts. Utilizing organic materials allows for smaller and faster semiconductor devices. But, it also creates a demand for better manufacturing methods in order to maintain quality and product yield. OSM devices are allowing the next generation of semiconductor products to advance forward and, at the same time, simplifying the manufacturing process. As OSM devices advance forward, so too must the semiconductors used to control these new OSM devices. Transistors are commonly used to provide this control. Despite being a revolutionary breakthrough when invented, the transistor is not always the ideal solution when simpler technology is the better solution. It is likely that great strides can be made in the semiconductor evolution as further progressions are made in this area.
Generally, the control of a semiconductor device is accomplished through the utilization of electricity. A voltage is placed across the device to put it in a predetermined state, thus “controlling” it. Depending on the device being subjected to the voltage, it may store a value represented by the state or it may turn the device ON or OFF. If the device is a memory cell, it may be programmed to read, write or erase based on the voltage level and polarity. If the device is an LED, application of the voltage may turn the emitter ON or OFF, reduce its brightness or increase its brightness. Thus, it is imperative for proper operation of these types of devices that there is a means to control the application and level of the voltages across them. Current manufacturing techniques utilize additional external semiconductor devices for this purpose, such as transistors. These transistors are somewhat complex devices that require a multitude of fabrication steps to produce.